California's Insanity Defense
The M'Naghten Rule
Do you have a love one who suffers from mental health issues, but who is accused of a crime?
We're a criminal defense law firm with experience helping mentally impaired clients assert "Not Guilty by Reason of Insanity" as a legal defense in California.
Under the M'Naghten rule, California law judges a person legally insane if he is incapable of distinguishing between right and wrong or doesn't understand the nature of his acts. In cases of insanity, a defendant is determined not guilty of the crime and is committed to a state mental hospital rather then prison.
Below, our California criminal defense attorneys1 discuss the following:
1. The Legal Definition of Insanity
(The M'Naghten Test)
1.1. The history of the M'Naghten test
1.2. Proposition 8 and Penal Code 25 PC
2. Proving Insanity as a Legal Defense
in California
2.1. Preponderance of the evidence -- the defendant's
burden of proof
3. How and When to Enter a "Not Guilty
by Reason of Insanity" Plea
3.1. Entering a "dual" plea of "not guilty" and "not guilty
by reason of insanity"3.2. Sanity hearings in California
3.3. Enter a single plea of "not guilty by reason of
insanity"
4. Sentencing (Commitment in a State
Mental Hospital vs. Punishment)
4.1. The purpose of commitment
If, after reading this article, you would like more information, we invite you to contact us at Shouse Law Group.
You may also find helpful information in our related articles on California Legal Defenses; The California Criminal Court System; Arraignment Proceedings; Jury Trials; and Sentencing Hearings.
1. The Legal Definition of Insanity
(The M'Naghten Test)
California law declares a person "legally insane" if he/she
- doesn't understand the nature of his/her act, or
- can't distinguish between right and wrong.
This test, known as the M'Naghten rule (sometimes spelled M'Naughton), is the current test that California…as well as a number of other states…use to define insanity. If the court finds a defendant to have been legally insane at the time of an alleged crime, he/she will be pronounced not guilty by reason of insanity.2 This wasn't always the case.
1.1. The history of the M'Naghten test
The M'Naghten rule is based on an 1843 case where the defendant Daniel M'Naghten attempted to assassinate the then British Prime Minister Robert Peel. During his trial, M'Naghten's attorney claimed that he was "driven to desperation by persecution" and that "his delusions had led to a break-down of moral sense and a loss of self-control which left him in a state where he was no longer a 'reasonable and responsible being'". The jury returned a verdict of not guilty by reason of insanity.3
The M'Naghten rule was then used throughout most of the world as the test for the insanity defense, though not in every country or even every state. Then, in 1978, the Supreme Court of California adopted another insanity test…the test used by the American Law Institute (ALI).4
The ALI's test states "A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality [wrongfulness] of his conduct or to conform his conduct to the requirements of law."5
1.2. Proposition 8 and Penal Code 25 PC
Then in 1982, the people of the state of California passed Proposition 8, known as the "Victims' Bill of Rights", which enacted Penal Code 25 PC. As it pertains to California's insanity defense, Penal Code 25(b) reads
"In any criminal proceeding, including any juvenile court proceeding, in which a plea of not guilty by reason of insanity is entered, this defense shall be found by the trier of fact only when the accused person proves by a preponderance of the evidence that he or she was incapable of knowing or understanding the nature and quality of his or her act and of distinguishing right from wrong at the time of the commission of the offense".6
And even though Penal Code 25(b) PC states that the individual must be incapable of understanding the nature or his/her act AND of distinguishing between right and wrong, this is actually an incorrect statement of the law.7
As the California Court of Appeal explained in 1984, Proposition 8 reinstated the M'Naghten rule, which states that a defendant is legally insane if he/she is incapable of understanding the nature of his/her act OR is incapable of distinguishing between right and wrong.8 This test has remained unchanged and is still the test California uses today to determine insanity.
Example: Defendant believed that he was the victim of a medical conspiracy that treated him like a "human guinea pig". He believed that doctors had injected him with a mysterious virus that was killing him and making him "rot alive" and give off a stench that made him socially unacceptable. As a result, he went to USC County Hospital in order to shoot and kill doctors. He wanted revenge for the way they had treated him over the past ten years.
The judge in the case instructed the jury that in order to find the defendant insane, they must believe that he couldn't distinguish between right and wrong. The court further instructed that "wrong" referred to legal wrongs and moral wrongs, which was an incorrect statement of the law.
The expert psychiatrists who testified in the case believed that the defendant knew his acts were illegal but that he believed he had God's approval in committing them because they were morally necessary to eliminate evil and to protect himself and others from the doctors' illegal experiments.
As such, the psychiatrists believed that even though the defendant understood the nature of his act, he didn't understand that the act was morally wrong. This is why they believed that at the time of the crimes he was legally insane and why the court believed that the judge should have instructed using the conjunctive "or" rather than "and".9
2. Proving Insanity as a Legal Defense in California
California's insanity defense is what's known as an affirmative defense. And as Santa Ana criminal defense attorney Zachary McCready 10 explains, "An 'affirmative defense' is essentially a claim which the defendant makes that says 'even though I committed the crime, my conduct should be excused for the following reason…'".
Because it is the defendant who presents this defense, he/she also has the burden of proving it.11 Generally speaking, the prosecution has the "burden of proof" in a criminal trial. This means that the prosecutor must prove the defendant's guilt to the judge / jury. However, with an affirmative defense such as insanity, it is the defendant who must prove that he/she was insane at the time of the crime, and should therefore be excused from his/her criminal conduct.
2.1. Preponderance of the evidence -- the defendant's burden of proof
In a criminal case, the burden of proof typically lies with the prosecution and is the highest burden recognized by California's legal system. This burden is what's known as beyond a reasonable doubt. "Beyond a reasonable doubt" means to a moral certainty…that is, that the evidence is so strong that there is no logical explanation other than the fact that the defendant is guilty.12
When the defendant has the burden of proving that he/she is insane, his/her burden is only by a preponderance of the evidence, which requires a lesser showing. A "preponderance of the evidence" simply means that it is more likely than not that the defendant is insane.13
And it should be noted that phrases like mental illness, mental abnormality, below average intelligence, etc. are not synonymous with insanity. "Insanity"…as it applies to the insanity defense…is a legal term, not a medical one. If the mental state doesn't meet the M'Naghten test, it doesn't qualify as legal insanity.14 If it does meet the M'Naghten test, it doesn't matter whether the period of insanity was temporary…lasting only a few hours…or permanent…lasting several months.15
Example: During the defendant's marriage, her then husband would regularly "abuse, beat and vilify" her. This behavior frightened her to the point that she purchased a gun for protection. Defendant claimed that for about six years prior to the killing, she occasionally suffered from "spells" that would render her temporarily unconscious and in a seizure-like state. The fact that she suffered from these spells was confirmed by eyewitnesses.
Defendant presented evidence that…while she was "ordinarily sane"…she suffered from a spell at the time she killed her ex-husband, as she didn't remember anything about the incident. The jury believed her claim and found her not guilty by reason of insanity.16
3. How and When to Enter a "Not Guilty
by Reason of Insanity" Plea
There are two ways to pursue an insanity defense and both typically begin during the arraignment hearing.
3.1. Entering a "dual" plea of "not guilty" and "not guilty by reason of insanity"
The first way to enter an insanity plea is to enter two pleas -- one of "not guilty" and a second of "not guilty by reason of insanity". When a defendant enters a dual plea, he/she proceeds with a California jury trial in the same way as anyone else making his/her way through the California criminal court process.
Depending on the defense strategy, the defense lawyer will either 100% defend the charges or may defend the charges while at the same time offering evidence that his/her client had a mental illness that contributed to the crime. Either way, the actual issue of sanity is addressed in a separate trial. When issues are separated like this, the proceedings take place in what is known as a bifurcated trial.17
If the defendant is acquitted, he/she goes free and the case is over. If there is a hung jury…that is, the jury cannot unanimously agree on a verdict…the judge will determine if there is enough evidence to retry the case. If the defendant is found guilty, the case proceeds to a sentencing hearing…in this case, a "sanity" hearing.
3.2. Sanity hearings in California
During the sanity hearing, the defendant presents expert witnesses…typically psychiatrists…who testify that at the time of the offense, the defendant either
- didn't understand the nature of his/her act, and/or
- that he/she didn't understand that the act was wrong.
These are the only issues that are relevant during the sanity trial…and this is where the defendant has the burden of proving by a preponderance of the evidence that he/she was, in fact, insane at the time he/she committed the offenses.18
And it is important to note that a judge may remove the issue of insanity from the jury if the defendant has failed to present sufficient evidence on the issue.19
Example: Defendant entered dual pleas of "not guilty" and "not guilty by reason of insanity" to four counts of aggravated robbery. The jury found him guilty on all counts. During the sanity trial, the defendant claimed that he suffered numerous blows to the head throughout his life, which had caused Satan to take over his body. Other than his testimony about Satan, there was no other evidence to support his claim of insanity.
In fact, the two psychologists who examined him stated he was "making it up", knew the difference between right and wrong, and simply suffered from anti-social behavior. In addition, the prosecution played a conversation that had been recorded in jail between the defendant and his brother where the defendant claimed "I'm doing the homeless nut routine".
As a result, the judge granted the prosecutor's motion for a directed verdict…removing the issue from the jury's consideration…stating, the "defendant has failed to meet the burden of proving by a preponderance of the evidence that he suffered from a mental condition that rendered him incapable of knowing or understanding the nature and quality of his act, or incapable of distinguishing right from wrong in relations to that act".
The judge then sentenced the defendant accordingly.20
3.3. Enter a single plea of "not guilty by reason of insanity"
The second way to pursue California's insanity defense is to simply enter a plea of "not guilty by reason of insanity". If the defendant does this…and doesn't simultaneously enter a "standard" "not guilty" plea…he/she concedes that he/she is guilty of the offense. The only issues are therefore
- whether the defendant should be held responsible for his/her criminal conduct, or
- whether he/she should be absolved of criminal liability due to insanity.21
The court then conducts the sanity trial in the same manner set forth above.
4. Sentencing (Commitment in a State
Mental Hospital vs. Punishment)
Assuming the evidence is sufficient…and the jury deliberates the sanity case…a hung jury will result in the court making a determination as to whether there is enough evidence to retry the defendant on the issue of sanity only.
If the jury finds that the defendant was sane, he/she will be punished for the convicted offense(s) pursuant to the law. And even though the jury finds that the defendant was sane, the judge could still use any evidence of mental incapacity as a mitigating factor in sentencing the defendant.
If the jury returns a unanimous verdict of not guilty by reason of insanity, the defendant is committed to a state mental hospital.
4.1. The purpose of commitment
There are two reasons for commitment: (1) to rehabilitate and treat the offender, and (2) to protect the defendant and society from further harm.22 The defendant will remain institutionalized until
- doctors believe that he/she has regained sanity,
- the maximum term of incarceration has expired (this term is the same as the amount of incarceration that could have been imposed in connection with the underlying offense(s), or
- doctors believe outpatient status is appropriate.23
Call us for help…
For more information on California's insanity defense, or to discuss your case confidentially with one of our California criminal defense attorneys, do not hesitate to contact us at Shouse Law Group.
We have local criminal law offices in and around Los Angeles, San Diego, Orange County, Riverside, San Bernardino, Ventura, San Jose, Oakland, the San Francisco Bay area, and several nearby cities.
To learn about the Nevada defense of insanity, go to our page on the Nevada defense of insanity.
Legal References:
1Our California criminal defense attorneys have local Los Angeles law offices in Beverly Hills, Burbank, Glendale, Lancaster, Long Beach, Los Angeles, Pasadena, Pomona, Torrance, Van Nuys, West Covina, and Whittier. We have additional law offices conveniently located throughout the state in Orange County, San Diego, Riverside, San Bernardino, Ventura, San Jose, Oakland, the San Francisco Bay area, and several nearby cities.
2California Penal Code 25 PC -- Insanity as a California legal defense. ("… (b) In any criminal proceeding, including any juvenile court proceeding, in which a plea of not guilty by reason of insanity is entered, this defense shall be found by the trier of fact only when the accused person proves by a preponderance of the evidence that he or she was incapable of knowing or understanding the nature and quality of his or her act and of distinguishing right from wrong at the time of the commission of the offense.")
See also People v. Horn (1984) 158 Cal.App.3d 1014, 1032. ("Accordingly, we hold that Penal Code section 25, subdivision (b), reinstates the California M'Naghten right and wrong test as the standard for the insanity defense in this state."...")
See also California Jury Instructions, Criminal. CALJIC 4.00 -- Insanity as a California legal defense. ("A person is legally insane when by reason of mental disease or mental defect, [he] [she] was incapable at the time of the commission of the crime of one of the following: [1] Knowing the nature and quality of [his] [her] act; or [2] Understanding the nature and quality of [his] [her] act; or [3] Distinguishing what is legally right from what is legally wrong; or [4] Distinguishing what is morally right from what is morally wrong." Italics added).")
4People v. Drew (1978) 22 Cal.3d 333, 348. ("For the foregoing reasons, derived in large part from the analysis in Justice Mosk's concurrence, we now conclude that the California courts should employ the ALI test to define the defense of insanity.")
5See same at 345. ("The definition of mental incapacity appearing in section 4.01 of the American Law Institute's Model Penal Code represents the distillation of nine years of research, exploration, and debate by the leading legal and medical minds of the country. ( United States v. Freeman, supra, 357 F.2d 606, 622.) It specifies that 'A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality [wrongfulness] of his conduct or to conform his conduct to the requirements of law.'")
6California Penal Code 25(b).
7People v. Horn (1984) 158 Cal.App.3d 1014, 1032. ("For all of these reasons, we decline to interpret the statute as enacting a new drooling idiot test in place of the century old M'Naghten standard merely because it uses the single, and often misused, conjunctive "and." That conjunctive is too thin a reed to support such a massive doctrinal transformation.")
8See same at 1031. ("With regard to Penal Code section 25, subdivision (b), the guide at pages 8-5 and 8-6, concludes: "Essentially, this restores the traditional M'Naghten rule as to insanity, People v. Kelly (1973) 10 Cal.3d 565, 574, which was overturned by the California Supreme Court in People v. Drew (1978) 22 Cal.3d 333. [¶] While 'and' is used between the two phrases, although 'or' was used in the former test, there appears to be little practical difference between the former version of M'Naghten and the new structure." We agree with this assessment that the new statute "restores the traditional M'Naghten rule."")
9People v. Torres (2005) 127 Cal.App.4th 1391.
10Orange County criminal defense attorney Zachary McCready defends clients throughout Orange County, including Fullerton, Anaheim, Newport Beach, Santa Ana, Irvine and Westminster.
11California Evidence Code 522 -- Claim that person is or was insane. ("The party claiming that any person, including himself, is or was insane has the burden of proof on that issue.")
12CALJIC 2.90 -- Presumption of Innocence—Reasonable Doubt—Burden of Proof. ("Reasonable doubt is defined as follows: It is not a mere possible doubt; because everything relating to human affairs is open to some possible or imaginary doubt. It is that state of the case which, after the entire comparison and consideration of all the evidence, leaves the minds of the jurors in that condition that they cannot say they feel an abiding conviction of the truth of the charge.")
13CALJIC 2.50.2 -- Definition of Preponderance of the Evidence. (""Preponderance of the evidence" means evidence that has more convincing force than that opposed to it. If the evidence is so evenly balanced that you are unable to find that the evidence on either side of an issue preponderates, your finding on that issue must be against the party who had the burden of proving it.")
14People v. Coddington (2000) 23 Cal.4th 529, 608, overruled on other grounds. (""Mental illness and mental abnormality, in whatever form either may appear, are not necessarily the same as legal insanity. A person may be mentally ill or mentally abnormal and yet not be legally insane. "A person is legally insane when, by reason of mental disease or mental defect he was incapable of knowing or understanding the nature and quality of his act or incapable of distinguishing right from wrong at the time of the commission of the offense. The word 'wrong' as used in this instruction is not limited to legal wrong, but properly encompasses moral wrong as well. Thus, the defendant who is incapable of distinguishing what is morally right from what is morally wrong is insane, even though he may understand the act is unlawful."")
See also People v. Norton (1934) 138 Cal.App. 70, 74. ("Low mentality, is not, in law, insanity, and does not excuse one who otherwise is able to distinguish between right and wrong.")
15People v. Kelly (1973) 10 Cal.3d 565, 576-577. (""…[t]emporary insanity as a defense to crime is as fully recognized by law as is permanent insanity." (People v. Ford (1902) 138 Cal. 140, 141-142 [70 P. 1075].) Thus, if defendant at the time of the offense was insane under the California M'Naughton test, it makes no difference whether the period of insanity lasted several months, as in this case, or merely a period of hours. (See People v. Donegan (1939) 32 Cal.App.2d 716, 719 [90 P.2d 856].)")
16People v. Donegan (1939) 32 Cal.App.2d 716.
17California Penal Code 1026 PC -- Plea of insanity; separate trials; presumption of sanity; trial of sanity issue; verdict; sentence; confinement in state hospital or mental facility…("(a) When a defendant pleads not guilty by reason of insanity, and also joins with it another plea or pleas, the defendant shall first be tried as if only such other plea or pleas had been entered, and in that trial the defendant shall be conclusively presumed to have been sane at the time the offense is alleged to have been committed. If the jury shall find the defendant guilty, or if the defendant pleads only not guilty by reason of insanity, then the question whether the defendant was sane or insane at the time the offense was committed shall be promptly tried, either before the same jury or before a new jury in the discretion of the court. In that trial, the jury shall return a verdict either that the defendant was sane at the time the offense was committed or was insane at the time the offense was committed. If the verdict or finding is that the defendant was sane at the time the offense was committed, the court shall sentence the defendant as provided by law. If the verdict or finding be that the defendant was insane at the time the offense was committed, the court, unless it shall appear to the court that the sanity of the defendant has been recovered fully, shall direct that the defendant be confined in a state hospital for the care and treatment of the mentally disordered or any other appropriate public or private treatment facility approved by the community program director, or the court may order the defendant placed on outpatient status pursuant to Title 15 (commencing with Section 1600) of Part 2.")
See also People v. Hernandez (2000) 22 Cal.4th 512, 520. ("Under California law, if a defendant pleads not guilty and joins it with a plea of not guilty by reason of insanity, the issues of guilt and sanity are tried separately. Penal Code section 1026, subdivision (a), provides that in such circumstances, "the defendant shall first be tried as if only such other plea or pleas had been entered, and in that trial the defendant shall be conclusively presumed to have been sane at the time the offense is alleged to have been committed. If the jury shall find the defendant guilty, or if the defendant pleads only not guilty by reason of insanity, then the question whether the defendant was sane or insane at the time the offense was committed shall be promptly tried, either before the same jury or before a new jury in the discretion of the court. In that trial, the jury shall return a verdict either that the defendant was sane at the time the offense was committed or was insane at the time the offense was committed." Although guilt and sanity are separate issues, the evidence as to each may be overlapping. Thus, at the guilt phase, a defendant may present evidence to show that he or she lacked the mental state required to commit the charged crime. ( People v. Saille (1991) 54 Cal.3d 1103, 1111-1112 [2 Cal.Rptr.2d 364, 820 P.2d 588]; Pen. Code, §§ 21, 28, 29.) A finding of such mental state does not foreclose a finding of insanity.")
18See same at 521. ("The "sanity trial is but a part of the same criminal proceeding as the guilt phase" ( People v. Flores (1976) 55 Cal.App.3d 118, 122 [127 Cal.Rptr. 230]) but differs procedurally from the guilt phase of trial "in that the issue is confined to sanity and the burden is upon the defendant to prove by a preponderance of the evidence that he was insane at the time of the offense" ( id. at p. 121). As in the determination of guilt, the verdict of the jury must be unanimous. ( People v. Troche, supra, 206 Cal. at p. 44.)")
19People v. Severance (2006) 138 Cal.App.4th 305, 316-317. (""Where 'the evidence is uncontradicted or leads to a single conclusion a question of law is presented' [citation], and 'the trial court is not required to submit the question to the jury for a finding upon that plea' [citation]. Instead, the court may strike the plea [citation], or direct a verdict in favor of the prosecution or the defendant." (See, e.g., People v. Bechtel (1953) 41 Cal.2d 441, 445, 260 P.2d 31; People v. Wilson (1924) 193 Cal. 512, 514-515, 226 P. 5; People v. Newell, supra, 192 Cal. at p. 668, 221 P. 622.) There is no logical reason these same principles should not apply to a plea of insanity. Just as a criminal defendant may be "precluded from presenting to a jury defense such as unconsciousness [citation], diminished capacity [citation], [or] entrapment [citation], where there is insufficient evidence from which a reasonable jury could conclude that the particular facts underlying the instruction requested exist" ( People v. Mapp (1983) 150 Cal.App.3d 346, 350, 198 Cal.Rptr. 177), so a criminal defendant may be precluded, through the grant of a directed verdict, from presenting an insanity defense where the evidence is insufficient for a reasonable jury to find the defendant was insane at the time of his crimes.")
20See same.
21See People v. Hernandez at 521, endnote 17, above. ("The plea of insanity is thus necessarily one of "confession and avoidance." ( People v. Troche (1928) 206 Cal. 35, 44 [273 P. 767].) "Commission of the overt act is conceded" but punishment is avoided " upon the sole ground that at the time the overt act was committed the defendant was [insane]." ( People v. Wells (1949) 33 Cal.2d 330, 349-350 [202 P.2d 53], italics in original.)
22People v. Dobson (2008) 161 Cal.App.4th 1422, 1432. ("A successful insanity plea relieves the defendant of all criminal responsibility. ( People v. Jantz (2006) 137 Cal.App.4th 1283, 1295, 40 Cal.Rptr.3d 875.) The commitment of the defendant to a state hospital "is in lieu of criminal punishment and is for the purpose of treatment, not punishment. [Citation.]" ( People v. Superior Court (Williams) (1991) 233 Cal.App.3d 477, 485, 284 Cal.Rptr. 601 ( Williams ).) "The purpose of committing an insanity acquittee is two-fold: to treat his mental illness and to protect him and society from his potential dangerousness. [Citation.]" ( Wilder, supra, 33 Cal.App.4th at p. 101, 39 Cal.Rptr.2d 247.)")
23See same at 1432. ("A defendant found not guilty by reason of insanity may be released from a state hospital upon either (1) the restoration of sanity pursuant to the provisions of section 1026.2; (2) expiration of the maximum term of commitment, which means "the longest term of imprisonment which could have been imposed for the offense or offenses of which the person was convicted" (§ 1026.5, subd. (a)(1)); or (3) approval of outpatient status pursuant to the provisions of section 1600 et seq. (§ 1026.1; see People v. Soiu (2003) 106 Cal.App.4th 1191, 1194-1195, 131 Cal.Rptr.2d 421 ( Soiu ).)")
